Interstage steam superheating by means of high-pressure steam



Sept. 20, 1932; o, HARTMANN 1,878,135

INTBRSTAGE STEAM SUPERHEATING BY MEANS OF HIGH PRESSURE STEAM Filed June 5, 1928 ts-Sheet 1 OTTO H. HARTMANN P 1932- o. H. 'HARTMANN 1,878,135

INTERSTAGE STEAM SUPERHEATING BY MEANS OF HIGH PRESSURE STEAM Fild June 5, 1928 SSheets-Sheet 2 N- LL OTTO H. HARTNAN N Sept. 20 1932- o. H HARTMANN INTERSTAGE STEAM SUPERHEATING BY MEANS OF HIGH PRESSURE STEAM Filed June 5, 1928 3 Sheets-Sheet 5 OTTO H. HARTHANN 25 pressure.

Patented Sept. 20, 1932 E- STA S om'ro H. ,ii'AR'rMANN, or KAssEn-wILHnLMsHoHE, GERMANY, ASSIGNOR.:- 'ro SCHMIDTSCHE HEISSDAMIEF-GESELLSCHAFT MIT BESCHANKTER KASSEL-VIILHELIVISHOI-IE, GERMANY V HAFTUN G, OF

INTEESTAGE STEAM SUPERHEATING BY MEA S OF HIGHLPRESSURE sTEaM;

Applicationfiled June 5, 1923, Serial No. 283,055, and in Germany July 2, 1927.

My invention relates to apparatus for reheating interstage steam in power plants by means of high-pressure steam. In such arrangements, it has been usual'hitherto' either to allow the condensate from the heating steam to flow back under gravity to the highpressure boiler or to provide a special pump for its return. In the first case it is necessary, in order to obtain the necessary fall, to instal the reheater at such a height that in stationary plants the appearance of the engine room suffers. In portable installations, on the other hand, for example, locomotives and traction engines, in view of the limited height available, it is out of the question to instal the reheater at the necessary height. second case, it is desirable when possible to avoid the use of a pump for returning the condensate, on account of first cost, maintenance charges and working difliculties.

In order to overcome the above difficulties,

my present invention consists in leading back the condensate of the heating steam for the reheater into a vessel orcontainer at a lower The admission of the condensate into the vessel at a lower pressure can be controlled by some form of throttle device, or by a steam trap or the like, while the vessel or container itself can be inserted in the circulating system of the boiler feed-water.

In multi-pressure boiler installations, the condensate of the heating steam is preferably returned to a boiler section working at a lower pressure, or if the installation is provided with multi-stage feed-heating, the condensate may be led to one of the hotter of such stages.

Various advantages arise from my present invention. In the first place, from the point of view of thermal efficiency, the heat still present in the condensate of the heating steam is not lost but is usefully applied to the preheating of the boiler feed-water or to the heating of the water in the boiler itself. In addition, the use of a condensate pump is eliminated and it is possible to arrange the reheater in the foundations in'the case of a stationary installation, and below the boiler itself in the case of a locomotive.

The accompanying drawings show by way In the of example several forms of construction of the invention.

Figure 1 shows the arrangement as applied to an indirectly heated two-pressure marine installation, the two-pressure boiler being shown in longitudinal section;

Figure 2 is a cross-section on the broken line'IIII of Figurev 1;

Figure 3 is a longitudinal section of a twopressure locomotive;

' Figure 4 is a plan viewof the arrangement of the cylinders and the reheater, partly in section. 5

In the marine installation shown in Figures 1 and 2, the high-pressure steam is gen era-ted according to the indirect method in the upper Working drum 1, by means of a heat carrier which circulates in aclosed tube system and gives up its heat to the water q the workingboiler by help of heating elements 2, arranged in the drum 1. The heatreceiving part of the circulating tube system for theheat carrier consists of tubes 3, formmg the furnace flue, which are connected at their lower ends to collector headers 4, and at their upper ends to distributor headers 5. The latter, by means of risers: 6, and the former by downcomers 7 are. connected to the heating elements 2. The high-pressure M steam generatedin the boiler 1 is led byway of a. pipe 8, fittedwith ashut-off valve 23 through thesuperheater .10, arranged in. the reversing chamber 9 of'the boiler installation, to the high-pressurestagell oft'heengines, and after expansion therein exhausts through a pipe 24 to the intermediate stage 12; the exhaust from the latter 'stage is led through a pipe 13 .to a reheater 14:, from which the steam passes through a pipe 15 r to the low-pressure stage 16 of=the engines and thence through a pipe 25 to the condenser 23. The condensate is sucked by a pump 26 throughv a pipe 27 and'delivered through a pipe 28 to a hot water well 29 of known construction, from whichitis taken by. a feed water pump 30, and delivered through a. pipe 31 to the "low-pressure boiler 22. A feed waterpuinp 33 takes 'aportion ofthe water contained in the boiler 22, through apipe-34,

and delivers it to the high-pressure drum 1 through a conduit 35.

For reheating the interstage steam in the reheater 14 high-pressure and highly-superheated live steam is used, which is taken fromthe steam delivery pipe 17 from the. superheater 10 through a branch pipe 18,

leading toa serpentine or coil 19, in the reheater. The condensate of this heating steam is led by way of a steam trap 20, a throttle valve or the like and a pipe 21 into the water space of the smoke-tube boiler 22, serving as the low-pressure section of the installation and arranged in series with thehighpressure boiler as regards the fiue gases. As a lower pressure rulesin th s bo1ler than in the high-pressure boiler, the condensate of the heating steam flows tothe low-pressure boiler without the need of a pump. The lowpressure steam passes from the boiler. ,22 through a conduit 37, provided with a valve 38, to the superheater 36, arranged in the smoketubes of the boiler 22, and from the superheater36 through a pipe 39 to .the:pipe

pressure steam from said high pressure boiler to said reheater'to act as a heating medium first, means for conducting the exhaust from ,one stage of the engine to a later stage, said last named'means lncluding a reheater, means for conducting high pressure steam from said high pressure boiler to said reheater to act as a heating medium therein, and means for conducting the condensate of said high pressure steam formed in said reheater to said low pressure boiler.

In testimony whereof I ailix my signature.

. OTTO I-I. HARTMANN.

24 where it is mixed with the exhaust steam J from the high pressure stage and passes to the second stage of the engine.

In the locomotive shown in Figures 3 and 4 the same reference symbols are used to denote corresponding parts. .The exhaust steam from the high-pressure cylinder 11is led through a pipe 13 to the reheater 19, from which itpasses through conduits 15tov'alves Q low-pressure steam coming through pipes 39 from the low-pressure superheater 36. This steam mixture passes from the valves 40 to thelow-pressure cylinders 16. The exhaust steam from the cylinders 16 passes through conduits 41 to the blast pipe 42. The condensate of the heating steam is ledfrom the 140, where it is mixed with the superheated V heating coil 19 of thereheater by way of a steam trap .20 through a pipe 21 fittedwith a valve 43 to the smoke tube boiler 22.

For enabling the reheating of the exhaust steam of the high-pressure stage of the engine by means of high-pressure saturated steam a branch pipe 44 leading to the interstage superheater 19 and fitted with a valve 45 is connected with the pipe 8 conveying the live high-pressure superheater 10.

f Iclaim: a M

. 1. In a steam power plant, [a multistage engine, a boiler generating high pressure steam from the high-pressure drum 1 to the steam, a boiler generating low pressure'steam,

a superheater, means for conductingsteam from the high pressure :boiler through the superheater to the first stage of the engine, means for conducting steam from the low pressure boiler to a stage of the engine other than the first, a reheater, means for conducting the exhaust from said first stage of the engine through'the reheater to a stage other than the first, means for conducting high 

